DirectoryIndex index.php

<IfModule mod_rewrite.c>
  RewriteEngine On

  RewriteRule ^admin($|/) - [L]
  RewriteRule ^assets($|/) - [L]

  RewriteRule ^$ index.php [L]
  RewriteRule ^sitemap\.xml$ sitemap.php [L]

  RewriteCond %{REQUEST_FILENAME} -f [OR]
  RewriteCond %{REQUEST_FILENAME} -d
  RewriteRule ^ - [L]

  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteRule ^(.+)$ router.php?slug=$1 [L,QSA,B]
</IfModule>
